Check hardware integrity

Check the hardware integrity of your Ledger Nano S to check that the Ledger Nano S has not been tampered with. This article contains detailed technical information about the security of your device. 


Please handle the Ledger Nano S device with high care while you proceed. Be aware that once opened, your device will not be refundable or exchangeable.

Microcontroller (MCU)

The Secure Element checks the full microcontroller flash at boot, as described in this blog post. If it has been modified, you'll get a warning at boot. As an additional check, you can open the device to verify that no additional chip has been added (referring to the attached picture) and that the MCU is an stm2f042k6 (with 32 Kb flash, as a bigger flash could contain code fooling the Secure Element validation). Markings on the chip can vary but you should see the string "042K6".

Hardware revisions

Revision 1

  • Blue PCB
  • Black glue

Revision 2

  • Green PCB
  • Black or transparent glue [not pictured].

Revision 3

  • Blue PCB
  • Black glue

Revision 4 

  • Blue PCB
  • Hole in the PCB

Revision 5

  • Blue PCB


Revision 5 bis

  • Blue PCB

Revision 6

  • Blue PCB


Revision 7

  • Blue PCB
  • Thin display cable


Secure Element attestation

The Secure Element itself is personalized at factory with an attestation proving that it has been created by us. You can verify it by running

pip install --no-cache-dir ledgerblue
Then on firmware 1.3.1 or below
python -m ledgerblue.checkGenuine --targetId 0x31100002
Or on firmware 1.4.1 and above
python -m ledgerblue.checkGenuine --targetId 0x31100003

The source code is available here.  

Application verification

When opening an application, a Non Genuine warning is displayed if it is not signed by Ledger. A modified User Interface (as found in will also display a warning message on boot.

Root of trust

The root of trust for the current batch is the following secp256k1 public key :


- as checked here 

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